This is a strange question for me too. One is either circumcised or uncircumcised. Getting circumcised is also unlikely to be a fetish, as it is a one-time event.
The fetish and play-acting need not be about the surgery itself, but about imaginings, role-playing and pretending, about having to undergo preparations and examinations to determine it being applicable or not, about imagining the threat of being circumcised, of having older family members incessantly talking/threatening to have it done and them looking you over, in group or alone.
Or discussing the various kinds of circumcision, say for instance a trial or partial circumcision where only a small part of the tip of the foreskin is cut, with more perhaps to follow or maybe getting a lateral dorsal cut or a preparatory frenulum cut through to permit easier foreskin retraction instead of a circumcision.
Or being forced to retract the foreskin with a clasp of some sort as a preparation or trial prior to the procedure.
Once one has such an interest/fascination/obsession/fetish, the various permutations come easily to mind. If it doesn't interest you, then of course you won't imagine much.
And like so much discussed here, one needn't necessarily actually follow through with a fetish and have something definitely done. The imagining can often be sufficient.
I do suppose however that members who are already circumcised may have less interest in this, since they have already undergone circumcision.